To compare the relative central nervous system and cardiac toxicity of amoxapine, maprotiline, and trazodone with the older tricyclic antidepressants, a three-year (1981 through 1983) retrospective review was performed on 1,313 cases involving cyclic antidepressant exposures reported to the Maryland Poison Center. Seizures were more common in the amoxapine (24.5%) and maprotiline (12.2%) groups, compared with either the tricyclic antidepressants (3.0%) or trazodone (0%) (P less than .01). A higher incidence of seizures also was observed in desipramine ingestors (17.9%) compared with other tricyclic antidepressants. No significant differences in the incidence of central nervous system depression or cardiotoxicity was found between the groups. These findings support reports of an increased incidence of seizures in overdoses of amoxapine and maprotiline, but do not substantiate claims of less cardiotoxicity.